Propane container and method of making same



Dec. 24, 1963 w. L. LINDGREN 3,115,283

PROPANE CONTAINER AND METHOD OF MAKING SAME Filed July 3, 1962 2Sheets-Sheet 1 INVENTOR. W/W/Om L. Linc/grew 28 BY M %m a, TTORNEYS'Dec. 24, 1963 w. L. LINDGREN PROPANE CONTAINER AND METHOD OF MAKING SAME2 Sheets-Sheet 2 Filed July 3, 1962 INVENTOR. William L. L/hdgren Y A a,764'- AT RNEYS United States Patent Ofiice 3,ll5,233 Patented Dec. 24-,1963 3,115,283 PRGPANE C(BNTAHNER AND METHUD 9F MAKING SAME William L.Lindgren, Sycamore, llL, assignor to Turner Corporation, Sycamore, lll.,a corporation of lllinois Filed duly 3, 1%2, Ser. No. 207,237 7 Claims.(ill. 222-3969 This invention relates generally to a fuel cylinderassembly and to a method of making the same wherein a drawn tank havinga pierced opening formed as an embossment carries a bushing memberproduced as a separate article of manufacture and which is characterizedby a center valve pas-sage with inner and outer concentrically disposedrings at the outermost end of the bushing to facilitate assembly of aplastic coupling member thereto and also providing a greatly reducedsealing area inwardly of the inner ring to facilitate filling of thetank.

It is an object of the present invention to provide a fuel cylinderassembly which utilizes axially adjacent connected-together plastic andmetal bushing pants wherein the only function of the plastic bushing isto effect a coupling action.

Another object of the present invention is to provide an inletconstruction for a fuel cylinder assembly wherein to essential sea-lingaction is effected by a unitary metal bushing brazed to the tank toestablish and maintain the integrity of the sealed joint, therebyavoiding the necessity of mixing materials as is frequently necessitatedby the utilization of a crimped gasket-carrying structure.

A further object of the invention is to provide an im proved tankfabricating process wherein a brazed bushing provides a greatly reducedsealing area to facilitate filling of the tank with fuel.

A still further object of the present invention is to provideinterconnected plastic and metal bushings wherein the plastic bushing ischaracterized by a recessed lip and the metal bushing has acorrespondingly offset ring filling the recess of the lip, thereby tominimize the weakness of the weakest cross-sectional point on theplastic bushing.

Many other features, advantages and additional objects of the presentinvention will become manifest to those versed in the art upon makingreference to the detailed description which follows and the accompanyingsheet of drawings in which a preferred structural embodiment of a fuelcylinder assembly incorporating the principles of the present inventionwill be shown by way of illustrative example.

On the drawings:

FlGURE l is an exploded view showing the details of r construction ofthe independently produced articles which are ultimately combined toprovide the fuel cylinder assembly of the present invention and by meansor" which the steps of the method of the present invention may becleanly understood;

FIGURE 2 shows all of the components of FIGURE 1 in final assembledrelationship and with the pusher pin of a fuel-consuming appliance inposition to actuate the movable stem of the valve; and

FIGURE 3 is a reduced fragmentary view of a fuel cylinder assemblywherein the bushing construction of the present invention is capped forcleanliness and ready for sale and distribution.

As shown on the drawings:

In accordance with the principles of the present invention, a fuelcylinder is provided which is shown generally at ill and which mayinclude an upper portion T1, at lower portion 12, and a "foot ring 13.The upper and lower portions are joined together at a seam l4 and eachmay be formed by a suitable drawing operation, thereby changing theshape of a metal blank into a cup-shaped article suitably proportionedso that the upper Mid lower portions together form a .fuel tank, asillustrated in FIG- URE 3.

The drawn upper portion ll is particularly characterized by the piercingof a center aperture therein shown at 16 and which is preferably formedas an embossment l7 turned inwardly towards the interior of: the fuelcylinder 10. The embossment l7 has a curved surface configurationidentified in FIGURE 1 at 18.

Formed as a separate article of manufacture by screw machine fabricatingtechniques, is a metal bushing shown generally at 20. The bushing 2i} isparticularly characterized by a generally cylindrical body portion 21and a tapered inner end 22.

At the top of the body portion 21 there is a radially outwardlyextending flange 23. Between the cylindrical body portion 21 and theflange .2 3 there is formed a curved peripheral surface 24 whichconforms in shape with the curved surface 18 of the embossment l7. Thecylindrical body portion 21 is preferably of the same size as thecentral opening l6 pierced in the upper wall of the fuel cylinder 10.

In order to place the metal bushing 24} in firm assembly with the fuelcylinder ill, a suitable copper razing material is placed on thesurfaces 18 and and the two components are subjected to controlledtemperature conditions as in a brazing furnace to complete asealedtogether bonded assembly forming a copper brazed sealed join-tindicated in FIGURE 2 at 26.

The bushing 29 is particularly characterized by a through passage 27. Atthe innermost end of the passage, there is an inwardly tapered portion28 which forms a seat for a correspondingly tapered portion 29' on atire valve shown generally at 30.

Above the tapered portion 28 in the passage 27, there is formed an innerthreaded portion 31 which receives in threaded-together relation thecorrespondingly threaded portion 32 of the tire valve 30.

The passage 27 is counterbored as at 33, thereby forming a radialshoulder 34.

After the bushing 20 has been placed in firm assembly with the fuelcylinder if the tire valve 38 is screw-threaded into assembledrelationship and the tapered portion 29 seats securely against thecorrespondingly tapered portion 28 of the bushing 29. At this point inthe fabricating procedure, it is already possible to test the assemblyfor leaks. The fact that the bushing 26 is assembled by brazing in thepierced opening in insures the integrity of the joint. Further, by usingthe brazed joint 26 and the direct metal-to-metal relationship of themetal bushing 2% with the embossed walls of the fuel cylinder 10, thereare no mixed materials such as occurs with other prior art constructionswherein metal parts are sometimes crimped together in association withsealing gaskets and other sealing materials.

At this point in the fabricating procedure, it is also possible to fillthe fuel cylinder lid with fuel, for example, propane or any otherdesired fuel required to be used in the fuel cylinder 10. In thisregard, note that the shoulder 34 at the bottom of the counterbore 33provides a greatly reduced sealing area which facilitates filling of thetank at reduced unit pressures and without the difficulties which areinherent in fuel cylinder assemblies utilizing crimped joints.

The bushing 26 is particularly characterized by the formation of innerand outer rings shown at 36 and 38, respectively. The inner ring 36immediately surrounds the counterbore 33. The outer ring 38 isconcentrically disposed with respect to the inner ring 36 and is inupstanding relation relative to the flange 23. Thus, the inner and outerrings 36 and 38 together form an annular recess 39.

An 0 ring sealing member 4% is provided which has an outer diametersized to engage the side walls of the counterbore 33 and an innerdiameter sized to engage the outer peripheral surface of the pusher pin4-1 shown in FIGURE 2 as entering the passage 27.

In order to couple the fuel cylinder assembly it? to a fuelconsumingappliance, there is provided a coupling member made of a plasticmaterial and shown generally at 42. The coupling member 42 is ofgenerally cylindrical configuration and includes a ring-shaped bodyportion 453 which is externally threaded as at 44. A center passage asis rovided which is counterbored as at 47. The body portion 43 has anupper face 43 and a lower radial face 49 which is characterized by adepending annular lip St The lip Silt has a radial inner wall 51prescribing a circular configuration conformably shaped to the innerring 36. In this regard, an annular recess 2 is formed at the bottom ofthe opening 51 and it may be noted that the passage 46 is of lesserdiameter than the ring 46, thereby providing an annular shoulder 53which serves to retain the O ring 46 in assembled relation within thecounterbore 33.

The lip 53 has a radial end face 54 and an outer peripheral wall aswhich tapers radially inwardly, thereby to form a recess '1. The widestportion of the lip 50 at the end face 54 is of such a dimension as to bereadily received within the annular recess 39.

Accordingly, after the O ring 4%) is inserted into the counterbore 33,the bushing is placed in position with the lip 5% received within theannular recess 39 and the outer ring 325 is offset radially inwardly bycrimping as shown in FIGURE 2.

Because of the recessed lip construction, the plastic bushing 42 and themetal bushing 2i) are pulled together axially so that the two parts areclamped tightly in axial direction by the crimping operation. Further,the shape of the recessed lip 59 and the cooperation therewith of theouter ring 33 minimizes the weakness of the weakest cross-sectionalpoint by, in effect, filling the reduced area with the metal of thebushing 20. Thus, the plastic coupling member 42 need only function as acoupling member and is not necessary to establish or to maintain any ofthe seals required for the proper utilization of the fuel cylinder witha fuel consuming appliance.

A cup-shaped paper cap 64) is assembled over the bushing constructionand the completed fuel cylinder assembly is then ready to be shipped.

In usage, the pusher pin 41 of the appliance will enter the passage 27and engages against a valve stem 61, thereby to admit fuel from the fuelcylinder lil into the passage 27.

Although minor modifications might be suggested by those versed in theart, it should be understood that I wish to embody within the scope ofthe patent warranted hereon all such modifications as reasonably andproperly come within the scope of my contribution to the art.

I claim as my invention:

1. A fuel cylinder assembly comprising,

a tank having an embossed opening formed therein,

a bushing in said opening,

a circumferential joint sealing and retaining said bushing in said tankin firm leak-proof assembly with one another,

a tire valve confined in said bushing to control the outward flow offuel therethrough,

said bushing having upstanding inner and outer rings forming an annularrecess,

and a ring shaped coupling member having a passage extending axiallytherethrough affording access to said tire valve for effecting dischargeof fuel from said tank,

said coupling member being made of nylon material and including athreaded coupling portion and a circumferentially extending lipprojecting from one radial face thereof,

said lip projecting into said annular recess,

said outer ring being offset radially inwardly to confine said lipbindingly between said inner outer rings and to retain said couplingmember in firm assembly with said bushing.

2. in combination,

a valve having a valve body through which pressurized fluid is directedand a valve stem actuator projecting axially out of one end of saidvalve body,

a metal cylindrical bushing screw threaded to said valve body and havinga flow passage extending axially of said valve stem actuator,

said bushing having a radially outwardly extending flange,

a cylinder for containing a supply of pressurized fluid and having anopening formed therein,

said cylindrical bushing projecting into said opening and said flangeoverlying the edges of said opening,

a circuinferentially continuous joint connecting said flange inleak-proof assembly with said cylinder,

said flange having upstanding inner and outer concentrically spacedrings,

and a ring shaped coupling member having a passage extending axiallytherethrough for affording access to said valve and said valve stemactuator,

said coupling member having upper and lower radial faces and anexternal-1y threaded peripheral coupling portion, said 'lower facehaving a circumferentially extending lip projecting therefrom betweensaid inner and outer rings, said lip having an outer peripheral wallwhich is recessed radially inwardly, said outer ring being offsetradially inwardly into the recessed portions of said outer peripheralwall, said lip having an inner wall tightly engaging said inner ring,whereby said lip is bindingly confined between said inner and outerrings.

3. A fuel cylinder assembly comprising,

a tank for containing a supply of fuel under pressure and having anopening formed in a wall thereof through which the fuel is discharged,

a valve having an axially movable actuator stem in said opening tocontrol the discharge of the fuel,

a generally cylindrical metal bushing threadedly con nected to saidvalve and having an axial body portion extending through said openingand a radially outwardly extending flange portion overlying the edges ofsaid opening,

a circumferentially continuous joint connecting said flange and saidtank in sealed tight assembly,

said bushing having an axial passage formed with a counterbore at theend thereof,

an O ring sealing member received in said counter bore for sealingagainst the walls of said passage a adapted to seal against theadjoining surface of a pusher pin when extended through said axialpassage for engagement with said actuator stem and for carrying fueldischarged by said valve,

inner and outer axial rings on said flange forming an annular recesstherebetween,

said outer ring being offset radially inwardly,

and a nylon bushing having external peripheral coupling threads forengagement with a fuel consuming appliance and an axial passage throughwhich the pusher pin may be extended,

said nylon bushing having a depending lip with,

circumferentially extending inner and outer axial. walls,

said inner wall tightly engaging said inner ring: and said outer walltightly engaging said offset outer ring,

whereby said lip is bindingly confined between said inner and outerrings.

4. A fuel cylinder assembly defined in claim 3,

said nylon bushing having abutment means extending radially inwardly ofsaid inner ring to confine said 0 ring sealing member in saidcounterbore.

5. A fuel cylinder assembly as defined in claim 3 and furthercharacterized by said outer Wall of said depending lip being preformedto taper radially inwardly with the Widest portion of the lip seating inthe bottom of said recess,

whereby the shape of the lip and the cooperation of the outer ringeffectively fills the reduced area with the metal of the bushing.

6. A fuel cylinder assembly as defined in claim 3 wherein saidcircumferentially continuous joint comprises a copper brazed connection.

7. A fuel assembly as defined in claim 3, said tank having the edges ofsaid opening formed as an inwardly turned embossment and said bushing 5having the adjoining axial body portion and flange conformably shaped toengage said embossrnent, said opening and said axial body portion beingof the same size.

10 References Cited in the file of this patent UNITED STATES PATENTS

1. A FUEL CYLINDER ASSEMBLY COMPRISING, A THANK HAVING AN EMBOSSEDOPENING FORMED THEREIN, A BUSHING IN SAID OPENING, A CIRCUMFERENTIALJOINT SEALING AND REATINING SAID BUSHING IN SAID TANK IN FIRM LEAK-PROOFASSEMBLY WITH ONE ANOTHER,